Musical instruments having instrument strings comprising a core wire around which is disposed a wrap wire are very common. Typically, such “wound strings” are used for strings providing the lower notes on the instrument. For example, wound strings are typically used on all strings of a bass guitar, the four bass strings of a steel-string acoustic guitar, the three bass strings of a six-string electric guitar and the four bass strings of a seven-string electric guitar.
Also, it is common for stringed musical instruments to amplify the sound provided by such instruments. A common way of providing amplification is by disposing the strings of the instrument over a pickup. A pickup device acts as a transducer that captures mechanical vibrations from the strings, and converts them to an electrical signal which can be amplified, recorded and/or broadcast.
One of the most common type of pickup is a magnetic pickup. A magnetic pickup consists of a permanent magnet wrapped with a coil of fine enameled copper wire. The vibration of nearby soft magnetic strings modulates the magnetic flux linking the coil, therefore inducing an alternating current through the coil. This signal is then sent on to amplification or recording equipment.